In almost every place where we find totems we also find a law against persons of the same totem having sexual relations with one another and consequently against their marrying. This, then, is 'exogamy', an institution related to totemism.

My psychoanalysis has equipped you with the equivalent of a train ticket to recovery. It is now your decision whether or not you choose to make full use of it.

It is unreasonable to expect science to produce a system of ethics-ethics are a kind of highway code for traffic among mankind-and the fact that in physics atoms which were yesterday assumed to be square are now assumed to be round is exploited with unjustified tendentiousness by all who are hungry for faith; so long as physics extends our dominion over nature, these changes ought to be a matter of complete indifference to you.

We find a place for what we lose. Although we know that after such a loss the acute stage of mourning will subside, we also know that we shall remain inconsolable and will never find a substitute. No matter what may fill the gap, even if it be filled completely, it nevertheless remains something else.

If there are quarrels between the parents or if their marriage is unhappy, the ground will be prepared in their children for the severest predisposition to a disturbance of sexual development or to neurotic illness.

The motive forces of phantasies are unsatisfied wishes, and every single phantasy is the fulfillment of a wish, a correction of unsatisfying reality.

The only shame in masturbation is the shame of not doing it well.